1. Technical Field
The present invention generally relates to electronic devices and in particular to temperature control in electronic devices. Still more particularly, the present invention relates to leakage currents and temperature control in electronic devices.
2. Description of the Related Art
When microelectronic devices are operated within the confines of their standard operating bias conditions, reliable performance is often restricted to a limited temperature range. In addition, these devices generally become unstable at low temperatures which limit the likelihood of reliable system startup, causing improper initialization and operation of the devices. As the technology evolves towards increased complexity and faster speeds, power dissipation resulting from the increased power densities of these devices become increasingly difficult to manage. The large amount of power (heat) dissipated by these complex devices is due in part to high quiescent leakage currents that are manifest by the large quantity and reduced lengths of parallel current paths inherent in the design of these devices. Excessive power levels lead to damaging high temperatures within the device, and cooling systems are employed to prevent temperatures from reaching destructive limits.
To further mitigate the problem of excessive power dissipation, operating voltages are reduced to a minimum value consistent with acceptable performance. However, this trend towards lower/minimum operating voltages appears paradoxical since higher voltages often imply improved performance due to higher noise margins. Thus, the useful range of function and performance is being traded off against reliability lifetime by restricting the limits of temperature and operating voltages. As operating voltages continue to be reduced in order to counter increased device power dissipation from increased power densities, rapid convergence of these mitigating processes (of reducing operating voltages and increasing power densities) towards a finite limit is apparent. New designs are tasked with managing the delicate balance between reducing operating voltages and increasing power densities to achieve increased functionality and/or performance over a maximized temperature range of reliable operation. As the trend continues, the balance becomes increasingly insurmountable and the range of reliable operation becomes proportionally more restricted.